Waste disposer rotor with yieldably biased teeth



United States Patent 1111 3,547,360

[ 72] Inventor George 0. Sherman, Jr. [56] References Cited Prairievillage, Kans- UNITED STATES PATENTS fg' g z f 2,220,729 11/1940 Powers241/4608 Continuation-impart of Ser. No. 471,769, r z f f July 13, 1965,Patent No. 3,436,027. [45] Patented Dec. 15, 1970 PrimaryExaminer-Robert C. Riordon [73] Assignee The Salvajor Company AssistantExaminer-Donald G. Kelly Kansas City, Mo. AIt0rneySchmidt, Johnson,Hovey, Williams & Chase a corporation of Missouri ABSTRACT: A rotor fora waste disposer comprising a relatively heavy base presenting aperipheral, upwardly extending wall and inturned lip defining aninwardly facing groove.

a g Grinding teeth having integral flanges projecting outwardly [S2]U.S. Cl 241/ 191, from the sides of the teeth are carried by the base sothat the 241/4608, 241/29l major forces directed against the teeth aretransmitted to the [54] WASTE DISPOSER ROTOR WITH YIELDABLY [51] lnt.Cl...B02c 13/28, base through the flanges. Resilient members engage eachB02c 18/40 tooth respectively to yieldably oppose movement of.the teeth[50] Field of Search away from their normal-grinding positions and aretainer plate 24l/(Rubber Elements in Mills Digest), 46.1,46.0 securesthe teeth and resilient members in position on the 46.08, l02, 191 2,257,259,291, l94,46, 193, 277 base.

PATENTED um 519m 354713 0 Fig.2.

INVENTOR George 0. Sherman Jr.

BY M

NEYS.

WASTE DISPOSER ROTOR WITH YIELDABLY BIASED TEETH CROSS REFERENCES Thisis a continuation-in-part of my copending application Ser. No. 471,769,filed July 13, 1965, now U.S. Pat. No. 3,436,027, issued Apr. 1, 1969,and entitled Waste Disposer."

This invention relates to waste disposer construction and, moreparticularly, to a novel rotor for a waste disposer. Conventionally, therotor carries a plurality of cutting or grinding teeth which cooperatewith an annular shredding ring for comminuting the waste material sothat the latter may be disposed through the sewer. The teeth normallyare situated relatively close to the shredder ring. Consequently,-aproblem often encountered in the operation of disposers of this type isthe jamming of the rotor as a result of relatively hard materialbecoming wedged between a tooth and the ring. Various means have beensuggested for alleviating the tendency of the rotors to become jammed.For example, the grinding teeth are often swingably mounted on the rotorso that they may pivot away from the grinding position when theyencounter objects capable of jamming the rotor. f

The swingable mounting of disposer grinding teeth detracts from theeffectiveness of the disposer. Also, the pivot means used in swingablymounting the teeth to the rotor requires complete disassembly of theunit to repair or replace worn or broken teeth. The pivotal coupling ofthe swingable teeth to the rotor is inherently weak and the teethareprone to break away from the rotor under the influence'of stressesimparted to the teeth during operation of the disposer.

Accordingly, it is an object of this invention to provide a rotorwherein the teeth are firmly supported against tilting or twistingstresses during operation, yet the teeth are permitted to move away fromthe shredder ring under the influence of stresses which would otherwisejam the disposer.

It is another object of the invention'to provide a waste disposer rotorconstructed in a manner wherein the grinding teeth are supported by arelatively heavy base member during operation so that the forces fromthe teeth do not distort or damage the other components of the rotor.

it is also an object of the invention to provide a rotor having grindingteeth which are relatively firmly held in normaloperating position butwhich will readily yield to avoid or release jamming forces.

Still a further object of the invention is to provide novelgrindingteeth configured to distribute the waste material evenly and uniformlyto the grinding surfaces of all of the teeth and at a rate whicheliminates the tendency to overload or jam any one tooth.

These and other objects of the invention will be further explained orwill become apparent from the specification, claims and drawing.

ln the drawing:

FIG. 1 is a top plan view of a rotor embodying the principles of thisinvention, parts being broken away to reveal details of construction;

FIG. 2 is a fragmentary, vertical cross-sectional view through a wastedisposer equipped with the rotor of H6. 1; and

FIG. 3 is a perspective view of one of the teeth used in the rotor.

The waste disposer is illustrated fragmentarily in FIG. 2 of the drawingand includes a generally cylindrical housing 12 provided with an annularshredder ring 14 mounted in the upper portion of housing 12 immediatelybeneath a neck section 16. The latter is adapted to be coupled-with asink or other waste receiver so that garbage and other kitchen wastesmay be flushed into the disposer 10.

The rotor 18 embodying the principles of this invention is mountedwithin housing 12 and is secured to the shaft 20 of an electric motor22. Rotor 18 comprises a circular, irregularly shaped, relatively heavybase 24. Base 24 is preferably cast as a homogeneous unit and includes adepending skirt 26 disposed in partial surrounding relationship tothe'upper end of motor 22 to provide an air seal to protect motor 22from water and other liquids handled by disposer 10.

Rotor 18 includes an integral, annular, peripheral rim 28 including anupright wall 30 and an integral, inturned lip 32 overlying the uppermostsurface 34 of base 24 at the outer peripheral margin of the latter. Lip32 and wall 30 define an annular, inwardly facing groove 36. The latteris adapted to receive the complemental outer edge 38 of outwardlyprojecting flanges 40 on each side of and integral with a tooth 42carried by rotor 18. It may be seen in H0. 1 that rotor 18 carries fouridentical teeth 42, each constructed as illustrated best in FIG. 3.

Each tooth 42 comprises an upwardly extending body portion 44, theopposed lateral faces of portion 44 sloping or tapering toward eachother as the innermost end of the tooth 42 is approached as illustratedclearly in FIG. 3. The outermost surface of body 44 is the grindingsurface and is disposed immediately opposite the cooperating grindingsurface of shredder ring 14 so that the waste material is comminutedbetween the grinding surfaces as the best teeth are rotated duringrotation of rotor 18 by motor 22.

Each tooth 42 is provided with an elongated rib 46 integral with andprojecting downwardly from the bottom of body 44 beyond the lowermostsurfaces of flanges 40. It may be seen in FIG. 2 of the drawing that theupper surface 34 of base 24 is provided with a channel 48 for each rib46, the latter being complementally received within its correspondingchannel for lending stability to the tooth.

Rim 28 is notched to permit each tooth 42 to project radially outwardlyfrom rotor 18 and into relatively closely spaced relationship fromshredder ring 14 during normal operation of the disposer. An elongatedmember 50 of resilient material is received between an outwardly facingshoulder of an upward annular projection 52 and the inner surface ofeach tooth 42. Projection 52 is integral with base 24. It may be seen inP16. 1 that there is a separate member 50 provided for each tooth 42.The members 50 may be formed of resilient material such as gum rubber orthe like, and the members 50'normally hold the teeth 42 in theiroperating positions. However, when the teeth 42 encounter forces whichmight otherwise jam the rotor, the yieldable nature of the resilientmaterial 50 permit the tooth to shift radially inwardly to release thejamming force and permit continued rotation of rotor 18.

A retainer or cover plate 54 is bolted to base 24 in overlyingrelationship to members 50 and the major part of the outwardly extendingflanges 40 of the teeth 42. The plate 54 is provided with radiallyextending, elongated slots 56 as illustrated best in FIG. 1. Slots 56cooperate with the ribs 46 and channels 48 to define the path ofshifting movement of each tooth 42 toward and away from its operatingposition. It will be noted that the slots 56 are longer than necessaryto accommodate the teeth 42. However, an upwardly extending boss 58integral with each member 50 projects upwardly into each slot 56immediately behind the corresponding tooth 42 to plug the gap betweenplate 54 and the innermost ends of the teeth 42. Manifestly, boss 58 isyieldable to permit inward shifting of the teeth 42 as mentioned above.Projections 60 integral with plate 54 provide impeller means forpartially comminuting and for directing waste material outwardly of therotor to the grinding surfaces.

In operation, the material of members 50 yieldably hold the teeth intheir grinding positions. The outermost arcuate edges of the flanges 40are received within the corresponding portions of groove 36 so that theoverhanging lip 32 prevents any twisting of the tooth. The forcesgenerated in the comminuting of waste material are transmitted from thetooth directly into the relatively heavy casting or base 24 which iscapable of withstanding the forces without a tendency to distort or tobecome damaged. Relatively little force is directed against the lightercover plate 54.

The spacing between the adjacent members 50 permits the latter to beinstalled between projection 52 and the proximal tooth by theapplication of tensile forces to each end of a member 50. This narrowsthe member so that it may be positioned easily, whereupon subsequentrelease of the member places the latter in compression betweenprojection 52 and against tooth 42. Since boss 58 is provided primarilyas a filler, it need notbe compressed against tooth 42. The compressiveforces of member 50 hold the grinding tooth relatively rigidly until, ofcourse, the tooth encounters forces sufficient to jam or break the rotorwhereupon the tooth is permitted to shift by virtue of the deformationof the material of member 50. Such shifting of the tooth immediatelyreleases the forces to obviate jamming or to prevent breakage ordamaging of the'rotor.

The sloping surfaces of body 44 provide that the leading surface of eachtooth is tapered rearwardly as the innermost end of the tooth isapproached. This permitsa portion of the waste material which engagesthe leading surface of the tooth to flow inwardly and rearwardly aroundthe tooth. Such flow prevents the teeth from becoming overloaded as aresult of the grinding of the material to the outer periphery of therotor under the influence of centrifugal force/Consequently, the excessmaterial is permitted to flow past, the inner end of each t'ooth thusequalizing the load on each tooth during the grinding operation.

The importance of the integral flanges 40 of the teeth 42 should not beoverlooked. These flanges provide lever arms extending outwardly in eachdirection from the centerline of the tooth to resist any twisting orbending forces acting upon the tooth. Accordingly, the teeth arenormally in their proper working positions and only move therefrom whenjamming or damaging forces are encountered. Should. the rotor becomejammed, it is merely necessary to reverse the direction of motor 22 andthe resilient forces exerted by members 50 permit sufficient withdrawalof the teeth to release the jam. Rotor I8 is constructed so that thedisposer may operate in the reverse direction with no loss of efficiencywhatsoever. In this connection, it is to be no'tedthat each side of eachtooth 42 is symmetrical withthe other side so that the leading surfaceof each tooth is tapered rearwardly regardless of the direction ofrotation of the rotor.

l claim:

A waste disposer rotor comprising: a rotatable base having an uppersurface; a peripheral rim extending upwardly from the surface, said rimhaying an inwardly facing groove; a grinding tooth shiftably carried onsaid upper surface; flange means integral with the tooth and .extendinginto said groove, the rim having a notch to permit projecting of thetooth from the base during grinding, the proximal edge of the flangemeans being received within the groove when the .tooth is in itsgrinding position for stabilizing the latter;

a resilient member carried by the base and engaging the tooth foryieldably biasing the latter into said grinding position; and

means carried by the base for securing the tooth and said member to thebase.

2. The invention of claim 1; said base including an upwardly extendingprojection presenting an outwardly facing shoulder, the member beinginterposed between the shoulder and the tooth.

3. The invention of claim 1, wherein said securing means includes aplate: said plate having an elongated slot extending radially of therotor and aligned with the notch of said rim; said tooth being receivedthrough the slot, the latter being longer than the. correspondingportion of the tooth to permit limited shifting of the latterlongitudinally of the slot toward and away from said grinding position.

4. The invention of claim 3: there being a plurality of teeth carried bythe base; said base having a notch and said plate having a slot for eachtooth respectively.

5. he invention of claim 4, wherein said flange means includes a flangefor, each side of the tooth respectively and integral therewith: eachflange extending outwardly from the corresponding side of the tooth;said groove in the rim being arcuate, the proximal edge of eachflangebeing complemental with the corresponding portion ofsaid groove.

6. The invention of claim 5: there being an elongated channel in saidupper surface of the base for each toothrespectively; each channel beinglongitudinally aligned with the corresponding slot in said plate; and arib on each tooth, integral therewith, said rib being received in thecorresponding channel to limit relative movementbetweenthe base and saidtooth to thelongitudinal direction of said channel.

7'. The invention of claim 4, wherein said member includes an upwardlyprojecting, resilient boss extending into the slot behind said tooth toyieldably resist movement of the tooth along the slot in the directionaway from said grinding position.

8. The invention ofelairnl, wherein said tooth includes an upwardlyprojecting, radially elongated body, said body having an upright,leading face disposed to engage waste materialduring rotation of,therotor saiddeading face tapering rearwardly as the radially innermostend of said body. is approached, whereby to permit inward movement ofwaste material along said tapered face during operation of the disposer.

9. The invention of claim 8, wherein said tooth is provided with asecond face on the opposite side of said body from said leading face:said second face being tapered toward said leading faceas the radiallyinnermost end of the body is approached; whereby topermit said inwardmovement of the waste material upon rotation of the base in eitherdirection.

